Jupiter Dec 28, 2012

Last night wasn't the greatest but I did get the Dob out to observe and try out eyepiece and barlow combos with my binoviewer. I was surprised that I could bump up the mag near 250x and get a good view with colors being exceptional in the northern hemisphere. When Jupiter climbed high enough to be in "Dobson's hole" the view deteriorated because of the atmospheric funk pouring into the tube, the fan not helping at this point. Oh well, it was late and I wanted to make the finished sketch.

The colors came out stronger than what I was actually observing (?), something Norme also experienced in one of his previous sketches. The NPC was pretty bland but showed a slight hint of blue. The NEB, NTZ and NTB displayed interesting colors. The NTB was a dark brownish color and was well defined. The NTZ was a yellowish tan color which blended into the NEB as orange, progressing into a dark maroon brown color. The SEB was equally interesting in that the color in front of the GRS was very dark brown, with lighter color toward the limb and light oval areas. The wake trailing the GRS was not as big as I have previously observed it, but the turbulence was definitely a blue color with light spots everywhere within. The SEB trailing the GRS was a light bluish grey color, starkly contrasting the colors of the leading part of the belt.

What a surprise the GRS was, displaying a pink hue that darkened toward the center. I haven't seen such color this apparition. I guess it's the STB that I was observing being pulled into the GRS. It was very prominent trailing the GRS, but almost imperceptible leading it. The color was a darkish grey. At the South end the cap was a light grey with hints of blue, and included very faint lighter streaks. There was a dark streak prominent that I believe is probably the South Temperate Temperate Belt (?) - I'm a lot newer at this than most of you, so I'm not sure about this one. Finally, I'm starting to see more pronounced shading in the limb (left side of sketch) now that Jupiter is past opposition. I noticed the same thing last year when observing Mars.

The hour or so that I was outside turned out pretty well and I was thrilled that I was able to see so much color in Jupiter last night.

Yes, IME, and for some reason I do not yet understand, the NEB give a a little more distinct red hue at 250x. Excellent description of that NEB reddish glow. To me it's just hard to nail down, but does appear to be reddish in the north as you say. I see it in good transparency, maybe that's what you had.

Not sure why the NPR appears blue at times, maybe our eyes are flirting with mesopic seeing and the rods add a little less red.

Yes, preceding and trailing the GRS, the belts take on a very different hue. To my eyes, deep brown and blue-gray, respectively. You captured the effect perfectly. I have to credit my girlfriend for pointing that out, she had no preconceived notion and was talking about "blue" where there /should have/ been none. She was right. It is stark once you see it, well done.

Also, seeing color across the GRS, IME, depends on transparency and probably seeing. It takes a good clear night to catch that. Sometimes it just appears gray with a "pink" northern border, other times it is entirely colorful. Color in BA is best seen in those conditions, too.

I am thrilled for you, too, Ed.

I am a little curious about the "Dob hole" allowing junk to pour down into the tube. It kind of makes sense, but I have never heard of it.

Norme, from all I read in other posts it appears the weather is pretty unique here in 'Sunny South Florida'. Although I'm in a very densely populated suburb I'm also not that far from the everglades, making for interesting local weather patterns. Right now there is mostly very high humidity and the air is a swirling mass of warm and cold that just doesn't seem to mix. On almost any given night I feel the bubbles of cold air dropping down on me while I observe. It's not too bad when the scope tube is at an angle, and the fan helps. But, when the tube is almost straight up it all drops down into the objective opening, the denser and more humid air wreaking havoc with the image. Imagine sitting there observing and someone pours a 5 gallon bucket full of light fog into the objective.

This is happening because now Jupiter is high up at the time when I can observe, and also because it's the time of year when we get all that hot/cold fluctuation along with the high humidity. On cold, crisp nights after a front has passed through and the atmosphere is stable I have had very good sharp and steady images with a cooled scope. (Cold for us is beach weather for y'all up north)

Ed, I like the way you have rendered the colors. I have had very little lucj with seeing much by way of color in the GRS, which I am now nicknaming the GPS (Great Pale Spot). Jupiter, however, is only at a maximum altitude of 30 degrees here, and seeing has not been great. Swap you some altitude for a little drier air???? :rollgrin: